Abstract Description
Quantitative sensory testing (QST) aims to rigorously assess nerve function. It is used in research of a wide range of patients with chronic pain, but the use is limited by high equipment costs, required training and time-consuming protocols.
Still, some patterns are commonly described: Thermal and mechanical detection thresholds are usually increased in patients with neuropathic pain, pinprick allodynia might indicate central sensitization, and pressure pain thresholds are often lowered in patients with musculoskeletal pain compared to pain-free individuals. Additionally, recent studies have linked the assessment of temporal summation of pain and conditioned pain modulation to treatment outcomes in patients with various forms of chronic pain. Additionally, within pain entities, sensory phenotypes can be used to stratify patients – a potential path to personalized pain management.
However, to bring QST to clinical routine use, bedside QST protocols are needed, using inexpensive equipment, simple protocols that can be applied without lengthy specialist training, and producing robust results. Here, we will present two complementary protocols. After an introduction into the basic principles and advancements of laboratory and bedside QST, we will also discuss new devices in the field. Jan Vollert and Roy Freeman will present the Boston protocol, and Manon Sendel the Kiel protocol.
Calibrated mechanical stimuli to assess perception of touch, pressure and sharp (pinprick) stimuli, can help identify the dysfunction in specific types of peripheral nerve fibers and muscles, particularly Aβ and Aδ fibers. In addition, pressure pain thresholds can help understand inflammatory processes occurring in deep (e.g. muscle) tissue. Tests for dynamic mechanical allodynia and temporal summation (wind-up) have an important role in understanding centrally-mediated phenomenta in neuropathic pain.
Calibrated mechanical stimuli to assess perception of touch, pressure and sharp (pinprick) stimuli, can help identify the dysfunction in specific types of peripheral nerve fibers and muscles, particularly Aβ and Aδ fibers. In addition, pressure pain thresholds can help understand inflammatory processes occurring in deep (e.g. muscle) tissue. Tests for dynamic mechanical allodynia and temporal summation (wind-up) have an important role in understanding centrally-mediated phenomenta in neuropathic pain.
Learning Objectives:
Upon completion, attendees will be able to:
- Describe the value of QST for assessing nerve fibre function comprehensively.
- Explain the challenges of translating laboratory QST to point-of-care and bedside settings.
- Apply two common bedside QST protocols in their research and practice.
- Describe the subtypes of nerve fibers that can be assessed with mechanical QST approaches – i.e. Von Frey monofilaments, Pinprick, and pressure algometer
- Outline common protocols for assessing mechanical detection threshold, mechanical pain threshold, dynamic mechanical allodynia, pressure pain thresholds, and temporal summation.
- Experience, hands-on, the measurements of mechanical sensation and pain thresholds as a participants, and as a tester; compare and contrast the anticipated vs real sense of participating in a sensory testing session as a subject.
